PROJECT(SUMMARY/ABSTRACT( (( Increasing evidence indicates that contacts formed between two major eukaryotic cellular organelles ? the endoplasmic reticulum (ER) and mitochondria ? are regulatory hubs essential for cell homeostasis. Although their pervasive significance for cell is established, they are poorly understood on both the molecular and functional levels ? a deficit that is directly addressed by this grant. Insight into the mechanisms of action, functional scope and modes of communication of ER-mitochondria contact sites will pave the way for a better understanding of the etiology of human diseases associated with mitochondrial and ER dysfunction and could reveal new targets for therapeutics.(